Turkey has called for an emergency NATO meeting of the alliance[4] following the incident and the meeting was due to take place on Tuesday, a diplomatic source said.

Turkey is a key member of NATO, whose charter stipulates that an attack against any member of the Western military alliance is considered an attack on all.

Syria has said it took out the F-4 phantom jet on Friday after it violated its airspace and on Saturday Turkey acknowledged that the plane may have done so in comments seen as a bid to cool tensions between the former allies.

In a statement issued after Syria confirmed it had downed the plane, Prime Minister Recep Tayyip Erdogan said Turkey would take all necessary steps once it had established the facts.

Turkey has become a major critic of President Bashar Assad over his crackdown on an uprising against his rule.

Armed opposition to Assad's rule have based themselves in Turkey, with the leader of the Free Syrian Army attempting to direct the insurgency from there.

But UN Secretary-General Ban Ki-moon said on Saturday that he hoped both sides would exercise restraint.

"The secretary-general is following the situation closely. He hopes this serious incident can be handled with restraint by both sides through diplomatic channels," Ban's spokesman Martin Nesirky said in a statement.

What do you think about Turkey getting NATO involved? Tell us your thoughts below.